Here's a video I made awhile back. It's me beating one of the bosses on "The World Ends With You" with Ultimate difficulty and set to level 1.

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As you can tell I love TWEWY, I've spent so many hours of my life into this game. I was going to do this with all the major bosses in the game but I needed to wait until I got the following things:

1. Better quality camera (the quality in the video above is horrible)
2. A way to record hands free. The game requires you to fight enemies on both screens which requires 2 hands alot of the time (the boss in the video above is pretty easy, I can defeat him with just the bottom screen).

Anyways I have made my own deck in the game. I like to call it the berserker deck because it doesn't allow most enemies to attack back. I also have the two best decks in the game (Eden and Black Planet). The Eden set makes Neku invincible but only when he has the puck of light (damage multiplier), and it starts the puck of light at 5x (the max amount). The Black Planet set it purely offense and when you have all 6 you can easily take out most enemies (I used this deck in the video).